The present invention relates to a chunks-of-concrete crushing device which also serves as a scooping device such as a bucket, a shovel or the like mounted on the distal end of a rotatable arm of an earthmover. Particularly, the present invention relates to a crushing device capable of crushing chunks of concrete into very fine pieces.
According to conventional crushing devices of this kind, chunks of concrete are crushed into equalized pieces in size, and thus, the efficiency of scattering pieces of crushed concrete is limited low. That means that in the conventional crushing devices, there are many cases where pieces of crushed concrete can not be scattered over to distant points as desired, and it is not possible to obtain pieces of various sizes.
It is an object of the present invention to improve the efficiency of scattering pieces of crushed concrete, and to enable obtaining easily as much fine pieces of crushed concrete as desired under particular operative circumstances.
The crushing device according to the present invention comprises: a bucket-shaped body frame; plural ring members provided in said body frame in such a manner as to form steps at predetermined spaced intervals while diminishing their sizes gradually from the upper position toward the lower position, thereby to form a sieve with gaps as a whole; a teeth plate provided at the bottom portion of said sieve and having recessed teeth and protrusive teeth alternately formed on the inner surface thereof; a crushing shaft provided at a central portion of said body frame; and an inclined screw belt member mounted on said crushing shaft, for crushing pieces of objects on said teeth plate in combination with said teeth plate.